Don't rely on EXEEXT as an env variable, infer it from --host instead

Dockerfile.cross

@@ -19,7 +19,6 @@ RUN apt-get update -qq && \
 ARG CROSS_ARCH=x86_64
 ENV CROSS_TOOLCHAIN_PREFIX=/opt/llvm-mingw-$CROSS_ARCH
 
-ENV EXEEXT=.exe
 ENV HOST=$CROSS_ARCH-w64-mingw32
 
 ARG FULL_LLVM
@@ -27,7 +26,7 @@ ARG FULL_LLVM
 COPY build-llvm.sh .
 RUN ./build-llvm.sh $CROSS_TOOLCHAIN_PREFIX --host=$HOST
 COPY strip-llvm.sh .
-RUN ./strip-llvm.sh $CROSS_TOOLCHAIN_PREFIX
+RUN ./strip-llvm.sh $CROSS_TOOLCHAIN_PREFIX --host=$HOST
 
 ARG TOOLCHAIN_ARCHS="i686 x86_64 armv7 aarch64"
 

build-cross-tools.sh

@@ -11,11 +11,10 @@ PREFIX="$2"
 CROSS_ARCH="$3"
 
 export PATH=$NATIVE/bin:$PATH
-export EXEEXT=.exe
 HOST=$CROSS_ARCH-w64-mingw32
 
 ./build-llvm.sh $PREFIX --host=$HOST
-./strip-llvm.sh $PREFIX
+./strip-llvm.sh $PREFIX --host=$HOST
 ./build-mingw-w64.sh $PREFIX --skip-include-triplet-prefix --host=$HOST
 ./install-wrappers.sh $PREFIX --host=$HOST
 ./prepare-cross-toolchain.sh $NATIVE $PREFIX $CROSS_ARCH

install-wrappers.sh

@@ -36,6 +36,10 @@ MINGW*)
     ;;
 esac
 
+if [ -n "$HOST" ]; then
+    EXEEXT=.exe
+fi
+
 if [ -n "$EXEEXT" ]; then
     CLANG_MAJOR=$(basename $(echo $PREFIX/lib/clang/* | awk '{print $NF}') | cut -f 1 -d .)
     WRAPPER_FLAGS="$WRAPPER_FLAGS -municode -DCLANG=\"clang-$CLANG_MAJOR\""

strip-llvm.sh

@@ -2,17 +2,33 @@
 
 set -e
 
-if [ $# -lt 1 ]; then
+unset HOST
+
+while [ $# -gt 0 ]; do
+    case "$1" in
+    --host=*)
+        HOST="${1#*=}"
+        ;;
+    *)
+        PREFIX="$1"
+        ;;
+    esac
+    shift
+done
+if [ -z "$PREFIX" ]; then
     echo $0 dir
     exit 1
 fi
-PREFIX="$1"
 cd "$PREFIX"
 
 if [ -n "$FULL_LLVM" ]; then
     exit 0
 fi
 
+if [ -n "$HOST" ]; then
+    EXEEXT=.exe
+fi
+
 case $(uname) in
 MINGW*)
     EXEEXT=.exe